Question

In the following number series, a wrong number is given. Find out the wrong number.

6, 15, 35, 77, 155, 221

1. 15
2. 35
3. 155
4. 221
5. 77

Answer 1

Correct Answer - Option 3 : 155

 6, 15, 35, 77, 155, 221

In this pattern,

⇒ 2 × 3 = 6

⇒ 3 × 5 = 15

⇒ 5 × 7 = 35

⇒ 7 × 11 = 77

⇒ 11 × 13 = 143

⇒ 13 × 17 = 221

∴ The wrong number in the pattern is 155